import json
import pygal_maps_world.maps
from pygal.style import RotateStyle
from pygal.style import LightColorizedStyle
from country_codes import get_country_code

# 将数据加载到一个列表中
filename = 'population_data.json'

with open(filename) as f:
    popdata = json.load(f)

# 打印每个国家2010年的人口数量
cc_populations = {}
for pop_dict in popdata:
    if pop_dict['Year'] == '2010':
        country_name = pop_dict['Country Name']
        population = int(float(pop_dict['Value'])) #Python不能直接将包含小数点的字符串 '1127437398.85751' 转换为整数

        code = get_country_code(country_name)
        if code: 
            print(code + ": "+ str(population)) 
            cc_populations[code] = population
        else:
            print('ERROR - ' + country_name)

# 根据人口数量将所有的国家分成三组
cc_pops_1, cc_pops_2, cc_pops_3 = {}, {}, {} 
for cc, pop in cc_populations.items():
    if pop < 10000000:
        cc_pops_1[cc] = pop
    elif pop < 1000000000:
        cc_pops_2[cc] = pop
    else:
        cc_pops_3[cc] = pop

wm_style = RotateStyle('#336699',base_style=LightColorizedStyle)
wm = pygal_maps_world.maps.World(style=wm_style)
wm.title = 'World Population in 2010, by Country'
wm.add('0-10m', cc_pops_1)
wm.add('10m-1bn', cc_pops_2)
wm.add('>1bn', cc_pops_3)
wm.render_to_file('world_population.svg')